Process of securing uniform revivification of activated carbon



Sept 7,1926. 1,599,072

(V. S. ALLIEN PROCESS OF SECURING UNIFORM REVIVIFIGATION OF AC'ILVATED CARBON Filed July 16. 1924 2 Sheets-Sheet 1 INVENTOR Victor/$411k, BY 12w W M ATTORNEYS Sept. 7 1926.

V. S. ALLIEN PROCESS OF SECURING UNIFORM REIVTVIPICATION OF ACTLVATED CARBON Filed July 16. 1924 2 Sheets-Sheet 2 INVENTOR IZZ'ZW'J. All 16% BY 7. ATTORNEYS Patented Sept. 7, 192 6 UNITED STATES PATENT OFFICE.

VICTOR S. ALLIEN, NEW YORK, N. Y., ASSIGNOR TO DARCO SALES CORPORATION,

. OF NEW YORK, N. 'Y., A CORPORATIOLT OF DELAWARE.

rnocnss or SECURING UNIFORM nnvrvIFIoA'rIoN or .AcrIvA'rm) CARBON.

Application filed July 16, 1924. Serial No. 726,288.

Particles of activated carbon which are used for the decolorizing or purification of liquids, as for instance sugar solutions, are

of irregular shape, and the efliciency in operation is in part dependent upon the surface area of the particles which is exposed for action to the liquid. The rapidity with which the particles may be filtered or otherwise separated from the liquid after treatment of the latter, is in part dependent upon the state of subdivision of the particles.

It is known that activated carbon after use may be revivified by a heat treatment. The main object of my invention is to subject the particles to the heating action in such a way as to get a maximum and uniform revivifying action with the minimum loss or deterioration.

In my improved process I so treat the particles that they are progressively advanced' through a series of heat zones of successively higher temperatures. In doingso I avoid abrading action which will tend to produce powdering or breaking up of the particles or the smoothing of the surfaces thereof. I absolutely prevent or carefully control the admission of air so as to avoid variable or objectionable combustion loss. I carefully control the temperature in the successive heat zones so as to permit-admis' sion' of the material to a zone of the desired low temperature, and the. final delivery of the material from a zone of the desired high temperature. I prevent contact of the materialwith the flame or gases of combustion and subject the material in comparatively thin layers to the action of heat from both above and below so as to secure uniformity of heating effect and free escape of moisture or other vaporizable'substances. I conduct from each heating zonethe vapors or gases-without passing them through orover the layers -of material in the other zones, and control the time of heat treatment in the successive heating .zones by giving to the material the desired speed of travel through said zones. I so utilize the heat that I secure the maximum economy of fuel with the minimum heat loss. I

My invention is not dependent upon the 'use'of any specific form of apparatus, it only being essentialthat "be apparatus be so designed as to permit the carrying out of the process.

In the accompanying drawings I have illustrated merely one form of apparatus which may be employed for carrying out my improved process.

' In these drawings:

Fig. 1 is a central vertical section, a portion beingin side elevation.

F g. 2 1s a transverse section, and

Fig. 3 is adevelopment on the semi-cin cular line 33 of Fig. 2.

In the accompanying drawings there is shown afurnace having a central supportmg structure for thematerial, and through which the heating gases are passed. Around this is a rotating structure which serves to advancethe material, and outside of this is the stationary protecting and sealing casmg. The center structure includes a series of superposed annular shelves or decks 10, each "of which has a chamber 11 therein, opening to a centrally disposed vertical flue 12 through which the heating gases pass. An inner flue 13 has a series of annular baffies 14 thereon, each of which extends out 4 lower end of the flue 13, and outside of the latter, so that the lower shelf is subjected to the highest temperature, and the temperature continually decreases toward the top.

To'avoid pockets or dead spaces at the outer edge or periphery of each chamber 11 there isprovided an annular passagelG below the supporting surface of each shelf 10, and at the peripheries of the several annular chambers 11. The inner wall of each passage 16 has a series of a ertures 16" therethrough'for the passage 0 gases from the chamber 11 into the passage, and each passage 16 is connected to the inner flue 13 by a radially disposed conduit 17 so that the gases which pass from the chambers 11 through the openings into the passage 16, may escape directly through the conduit. 17

to the inner, flue 13 without being caused of the shelf so that as the material is a(l-' vanced along the shelf to the opening 18 it may drop through to the shelf below. These openings 18 are so positioned in the several shelves that the material upon reaching a shelf is caused to travel along the shelf through nearly one complete revolution before it drops through to the shelf below. In other words, the openings are not invertical alignment but are arranged in progression. each opening being slightly in the rear. of the opening in the shelf above.

For advancing the material along the shelves there is provided a-rotatahle sleeve or frame structure 19 which has a plurality of inwardly or radially extending hlades20 carried therebv and properly juxtaposed to each shell". These blades are supported solely by the outer sleeve or frame 19, and do not rest directly upon the shelf but have a slight clearance so that they do not have any direct scraping or alirading action on the material. There are a large number of these blades for each shelf. so thatthe material on each shelf is acted upon by a series of the blades and kept in asubstantially uniform layer upon the shelf. The lower end" of the sleeve or frame 19 may be supported in any suitable manner, as for instance by roller bearings 21, and may be sealed at the lower end as for instance by extending into an annular water trough 22. It may also be held in proper axial alignment with the stationary structure by means of rollers 23. Any suitable means may be employed 'for rotating the frame which carries 'the scrapers. As

.shown, it has a peripheral worm gear 24 which may mesh with a worm in a casing 25 anddriven by a shaft 26. Eneircling the rotating parts is an outer stationary casing 27 which may be made of sheet metal and air-tight. The gear casing 25 may be secured to the outer casing 27 which may have a stufling box around the shaft 26 so as to prevmt the admission of any air at this point.

Above the upper shelf there is provided an annular plate 28 with a central opening communicating with'the upper end of the flue 12 and an outlet flue 29 may be connected to the upper end of this flue 12 so as to conduct from the outer casing the gases of combustion. The inner flue 13 may-terminate in an open end within and adjacent to the upper end of the flue 12 so that all or the gases of combustion which have passed nto the inner flue 13 through the several radial conduits 17 may unite with the other gases of combustion and escape through the flue 29'. i

" The top of the casing maybe connected to a conduit 30 through which the gases escaping from the material being treated may be drawn off to a condenser or separator, and this conduit may be connected with a vacuum pump if desired to thus subject the material to a partial vacuum during the heating action.

For delivering material to the furnace any suitable mechanism may be employed which will act to deliver measured quantities at the desired rate and prevent the admission of air. As shown, there is provided ahopper 31 delivering through a conduit 32, the lower end of which extends through the plate 28 to a point above the uppen shelf 10. At the lower end of the hopper there is provided a rotatable feeding device 33 which may he in the form of a drum having pockets therein so that as the drum rotates each pocket receives material when on the upper side of the drum and delivers it from the lower side. By varying the size of the pockets in the feeding mechanism the delivery of material may be accurately controlled. The speed of rotation of the feeding mechanism should be such that a separate charge isdelivered to the shelf as each blade 20 passes beneath the lower end of the conduit 32. The shaft 34 of the feed drum may be provided with a sprocket 35 which may be connected by a chain to a sprocket 36 on the shaft 26 which rotates the blades 20.

At the lower end of the furnace the material may pass from the lowermost shelf.

through an opening 37 to a chute 38 terminating below the surface of the water in a receiving chamber 39, and may be conducted from the latterby any suitable form cf conveyor 40.

In revivifying carbon the furnace may be so controlled that the temperature at the lower shelf will be 1100 F. to 1350 F., while at the top shelf it may be about 550 F. to 600 F.. The rotation of the blades should be comparatively slow, so that the material is given a gentle rolling motion without abrading action, and is advanced to shelves of successively increasing tempera- .ture. The outer stationary casing and the vertical series of shelves, permit the casing to be tapped at any points along its height for the controlled admission of steam, air or other gas to the material at any point along the path of said material, and where the material is at any desired temperature. The furnace permits of the careful admission orcomplete exclusion of air, as there is only one stufiing box and the remainder of the casing maybe easily constructed abso-- lute ly air-tight. The gentle sweeping or rolhng movementof the carbon does not Having thus described my invention,

what-I claim as new and desire to secure-- by Letters Patent is:

"1; The process of revlvifying activated carbon, whi h' consists in supporting it in comparatively thin-layers upon a series of superposed substantially flat and level .interiorly heated portions along the several shelves, and maintaining the shelves at successively higher temperatures from the upper to the lower.

2. The method of securing the uniform revivificationfl of activated carbon which includes supporting the material in a series of substantially fiat and level, annular, comparati'vely thin superposed layers,. moving the material by a gentlerolling motion in each layer in a substantially circumferential direction through nearly 360, and .then permitting it to drop to the next lower layer, interiorly heating the supports to dilferent temperatures, the lower support being heated to the highest temperaturfe, and-the heating medium being delivered to the supports in succession,

support to prevent the delivery thereof to the next succeeding support.

3; The method of securing uniform revivification of activated carbon which inshelves whereby the Ina-'- terial is out of contact with the heating means, advancing the material in separate and withdrawing a por-. tion only of theheating medium from each eludes supporting the material in a series of substantially flat and level, annular, comparatively thin superposed layers, moving each layer in a substantially circumferential direction through nearly 360, and then permitting it to drop to the next lower layer,-

and interiorly heating the supports to different temperatures, the lower support being heated to the highest temperature, and the heating medium being delivered to the supports in succession.

1. The process of revivifying activated carbon, which consists in supporting it upon a series of superposed substantially fiat and level interiorly heated shelves whereby the material is out of contact with the heating means, moving the material by a gentle rolling motion on each'shelf in a substantially circumferential direction through nearly 860 and then permitting it to drop to the the inaterial'by a gentle rolling motion in next lower shelf, and maintaining the shelves at successively highertemperatures from the higher shelf to the lower.

5. The process of revivifying activated carbon, which consists in supporting it upon a series of substantially fiat, superposed, an

nular shelves, moving the material by a a gentle rolling motion on each shelf in a substantially circumferential direction through nearly 360 andthen permitting it to drop to the" next lower shelf, and delivering a heating medium upwardly through the interior of the said shelves in succession and out of contactwith said material;

Signed at New York in the county of New York and State of New York this 14th day of July A. D. 1924.

. VICTOR S. ALLIEN. 

